Keyboard



FIG. 1 is a top, front, side perspective view of a keyboard;

FIGS. 2 and 3 are respectively front and back views thereof;

FIGS. 4 and 5 are respectively alternate side views thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings represent the portions of the keyboardthat form no part of the claimed design.

The ornamental design for a keyboard, as shown and described.